<template>
    请输入姓名:<input type="text" v-model="username">
    <div>姓名是:{{username}}</div>

    <input type="text" v-model.number="n1">+<input type="text" v-model.number="n2">={{ n1+n2 }}
</template>
<script setup>
import {ref} from 'vue'
const username=ref('张三')
const n1=ref(1)
const n2=ref(2)
</script>